Conventional torsion beam axles usually form a rear axle in the wheel suspension system of a vehicle. In motor vehicles, torsion beam axles are preferably combined with a front wheel drive. Such a conventional torsion beam axle is generally constructed of two longitudinal swing arms, on each of which one wheel of the vehicle axle is rotatably arranged. The longitudinal swing arms are connected to one another in a flexurally rigid manner via a torsion profile, which is oriented transversely with respect to a longitudinal direction of the vehicle. The torsion profile is configured in such a way that it is rotated within itself during compression and rebound of one of the longitudinal swing arms. As a result, the simple structural construction of a vehicle axle is made possible, in which the torsion profile acts as an anti-roll bar.
Suitable bearing arrangements are used to couple the torsion beam axle to the body of the vehicle. The bearing arrangements can contain a rubber/metal bearing in a usual way. The bearings are spaced apart from one another and lie between the longitudinal swing arms and the vehicle body, each forming a structural rotational axis around which the respective longitudinal swing arm can be pivoted.
As a result of the construction of a torsion beam axle of this type, the vehicle exhibits the tendency to oversteer when driving around bends. This is due, in particular, to the course of the rotational axes of the bearings, which predefine the possible movement direction of the longitudinal swing arms with respect to the vehicle. This is the case, in particular, when the individual rotational axes of the two bearing arrangements are aligned with one another. In order for it to be possible to perform a correction to the track of the wheels which changes during compression and rebound, which correction compensates for or at least attenuates the oversteering, corresponding solutions are already known in the prior art. For instance, the respective rotational axis of the bearing arrangements can be inclined, for example, by from 20° to 30° with respect to the vehicle transverse direction. This achieves a situation when driving around bends where the longitudinal swing arm on the outside of the bend is moved forward in the driving direction with respect to the vehicle during its compression. In contrast, the movement of the longitudinal swing arm on the inside of the bend takes place toward the rear.
However, due to the oblique position, the bearing arrangements of the torsion beam axle are then subject to increased wear. In addition, the required deformation of any elastic bodies within the bearing arrangement in combination with their rotation often produces undesired creaking noises.
The measures which are known in the prior art for reducing the oversteering tendency of the torsion beam axle usually require complicated designs. As a result, the space requirement for accommodation is usually increased. In particular, the arrangement of additional intermediate elements and pivot axes can impart an undesired hysteresis to the chassis. Also, the number of components which are subject to wear and the overall weight of axle designs of this type are increased. At the same time, the unsprung masses increase, which can have an undesirable effect on the driving behavior and, in particular, the comfort of the ride. Solutions which propose a special configuration of the rubber/metal bearings can likewise be considered to be complicated to produce and susceptible to wear. In addition, it is questionable to what extent the rubber/metal bearings alone can actually contribute to an improvement in relation to the oversteering tendency of torsion beam axles.
As discussed above, a satisfactory solution for reducing the oversteering tendency of torsion beam axles has not yet been identified. Against this background, the present disclosure is directed to improving a torsion beam axle in relation to its oversteering tendency. The novel design is lightweight, space-saving, simple to produce, and has a long service life, in particular in relation to the wear of the bearings. Furthermore, a bearing arrangement which improves the oversteering tendency for attaching the torsion beam axle to a body of a vehicle also is disclosed. The bearing arrangement is lightweight, makes space-saving and simple production possible and, in particular, has a design with a long service life in relation to the wear of the bearings.